Sökning: "thermal and oxidative degradation"

Visar resultat 1 - 5 av 6 uppsatser innehållade orden thermal and oxidative degradation.

1. 1. Service life study of environmentally friendly lubricants.

   Master-uppsats, Luleå tekniska universitet/Institutionen för teknikvetenskap och matematik

   Författare :Marybeth Chetachukwu Ugoh; [2023]
   Nyckelord :Base oil; Ageing; Glycerol; PPG; PEG; Squalene; Rapeseed oil; Ester; Paraffin; Oxidation; FTIR;

   Sammanfattning : Environmentally friendly lubricants are in demand in response to the rising concerns and restrictive legislation that surround the use of mineral oil lubricants. One area of importance is understanding the service life of the environmentally friendly base oils of these non-toxic, biodegradable and renewable alternatives. LÄS MER

3. 2. Lifetime prediction of a polymeric propellant binder using the Arrhenius approach

   Uppsats för yrkesexamina på avancerad nivå, Uppsala universitet/Tillämpad materialvetenskap

   Författare :Johannes Bohlin; [2021]
   Nyckelord :Polymer; Thermal-oxidative degradation; Lifetime prediction; Propellant; Arrhenius; Aging experiments; Diffusion-limited oxidation;

   Sammanfattning : The thermal-oxidative degradation of a crosslinked hydroxy-terminated polybutadiene (HTPB)/cycloaliphatic diisocyanate (H12MDI) based polymer, which is commonly used as a polymeric binder in propellants, is investigated at temperatures from 95°C to 125°C with the aim of estimating the lifetime of the material in storage conditions (20°C) using the Arrhenius approach. Furthermore, the effect of antioxidants and to a lesser extent plasticizer on the degradation process was also studied. LÄS MER

4. 3. Thermomechanical characterisation of newly developed UHMWPE composites

   Master-uppsats, Luleå tekniska universitet/Institutionen för teknikvetenskap och matematik

   Författare :Petra Jan; [2019]
   Nyckelord :UHMWPE; nanocomposites; thermomechanical characterisation;

   Sammanfattning : Ultra high molecular weight polyethylene (UHMWPE) is a polymer commonly used in various applications, particularly in hip joint replacements. Despite its good performance, it is susceptible to oxidation degradation, which can be mitigated with the addition of vitamin E, and to excessive wear against metal countersurfaces, which can potentially be improved with the addition of nanoparticles. LÄS MER

5. 4. Reprocessing and Characterisation of High Density Polyethylene Reinforced with Carbon Nanotubes

   Master-uppsats, Högskolan i Borås/Akademin för textil, teknik och ekonomi

   Författare :Sofie Svensson; [2017]
   Nyckelord :HDPE; mechanical recycling; carbon nanotubes; nanocomposites;

   Sammanfattning : Nanokomposit innehållande högdensitetspolyeten och kolnanorör återvanns och analyseradesför att undersöka hur materialets egenskaper påverkas av återvinning. Kompositenproducerades med 3 viktprocent kolnanorör och återvanns tio gånger genom att extrudera ochmala ner materialet. Analyser gjordes efter varje cykel av extrudering. LÄS MER

7. 5. Thermo-Oxidative Degradation of High Temperature Polyimide Composites : Characterization and Modeling of Composites Affected by an Extreme Environment

   Uppsats för yrkesexamina på avancerad nivå, Luleå tekniska universitet/Institutionen för teknikvetenskap och matematik

   Författare :Magnus Persson; [2016]
   Nyckelord :Polyimide composite material; thermal and oxidative degradation; glass transition temperature; stiffness modeling;

   Sammanfattning : Carbon fiber (CF) 8-harness satin weave, T650/Neximid system of [(+45/-45)/(0/90)]2S and [(0/90)]4S layup was manufactured using resin transfer molding (RTM). The material was cut into 3-point bending specimens and treated for 24 hours in a burn oven at T=(320,350,375,400,450 & 500)°C. LÄS MER